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Message-ID: <69e81208a2d301ea36f82802d10a29cff8c1e28a.camel@linux.intel.com>
Subject: Re: [PATCH] Revert "cpufreq: intel_pstate: Fix ->set_policy()
 interface for no_turbo"
From:   Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
To:     Gabriele Mazzotta <gabriele.mzt@gmail.com>,
        "Rafael J. Wysocki" <rafael@kernel.org>
Cc:     "Rafael J. Wysocki" <rjw@rjwysocki.net>,
        Len Brown <lenb@kernel.org>,
        Viresh Kumar <viresh.kumar@linaro.org>,
        Linux PM <linux-pm@vger.kernel.org>,
        Linux Kernel Mailing List <linux-kernel@vger.kernel.org>
Date:   Tue, 07 Aug 2018 14:22:24 -0700
In-Reply-To: <deeb4c4a-cdf5-02d2-8e06-4f1c2c88fb65@gmail.com>
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         <CAJZ5v0iwhVu6PwztsbN8cYmQtnjD2SyFkazkObc1o-1JX6GO5g@mail.gmail.com>
         <cd2287153b369d88cc240068adc7d341ef675acf.camel@linux.intel.com>
         <7195d55c-373d-23db-2744-ef3b1b719a5b@gmail.com>
         <8b51b0b832ba43ba1b22ddfc7b3094770ba4fe72.camel@linux.intel.com>
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On Tue, 2018-08-07 at 22:12 +0200, Gabriele Mazzotta wrote:
> On 07/08/2018 00:11, Srinivas Pandruvada wrote:
> > On Mon, 2018-08-06 at 23:50 +0200, Gabriele Mazzotta wrote:
> > > On 06/08/2018 18:49, Srinivas Pandruvada wrote:
> > > > On Mon, 2018-08-06 at 10:30 +0200, Rafael J. Wysocki wrote:
> > > > > On Sat, Aug 4, 2018 at 7:31 PM, Gabriele Mazzotta
> > > > > <gabriele.mzt@gmail.com> wrote:
> > > > > > On 04/08/2018 17:29, Gabriele Mazzotta wrote:
> > > > > > > This change does not take into account that some BIOSes
> > > > > > > change
> > > > > > > MSR_IA32is getting notified via PPC
> > > > > > > change._MISC_ENABLE_TURBO_DISABLE depending on the power
> > > > > > > source.
> > > > > > > If the turbo is disabled when the system boots,
> > > > > > > policy.max_freq
> > > > > > > is set to pstate.max_pstate. However, if the BIOS later
> > > > > > > enables
> > > > > > > the turbo, the CPU will never be able to run at
> > > > > > > pstate.turbo_pstate.
> > > > > > > is getting notified via PPC change.
> > > > > > > Since now intel_pstate_set_policy() does its calculations
> > > > > > > using
> > > > > > > pstate.max_freq and pstate.turbo_freq, we can always
> > > > > > > calculate
> > > > > > > cpuinfo.max_freq using pstate.turbo_pstate, thus allowing
> > > > > > > system
> > > > > > > with varying MSR_IA32_MISC_ENABLE_TURBO_DISABLE to run at
> > > > > > > full
> > > > > > > speed when the turbo is enabled.
> > > > > 
> > > > > Well, the problem with this approach is that always using
> > > > > pstate.turbo_pstate as the max causes the governor to
> > > > > overestimate
> > > > > the
> > > > > target frequency when the turbo range is not available (the
> > > > > target
> > > > > depends on the width of the entire available P-state range
> > > > > including
> > > > > turbo, so if the turbo range is not available, the number
> > > > > take
> > > > > into
> > > > > that computation is too large).
> > > > > 
> > > > > Are we expected to get notified when the BIOS updates
> > > > > MSR_IA32_MISC_ENABLE_TURBO_DISABLE?
> > > > 
> > > > Let's try this:
> > > > - boot with kernel command line 
> > > > 
> > > > intel_pstate=support_acpi_ppc dyndbg="file processor_perflib.c
> > > > +p"
> > > > dyndbg="file intel_pstate.c +p"
> > 
Can you create a bugzilla? In this way easy to exchange attachments.
For example in the above command line I was expecting boot up traces
from intel_pstate (I need full dmesg). From the log with PPC=6 should
correspond to 1.6GHz from acpi dump.
Even after power is connected the PPC is still requesting to be 6.

I will attach some test patch to bugzilla after checking the full
dmesg.


turbostat log shoes that turbo was disabled on unplug but it is getting
notified via some PPC change.

Thanks,
Srinivas

> > Interesting output.
> > Can you run ?
> > # turbostat --debug 
> > in both plugged and unplugged state.
> 
> This is the output of turbostat while plugged in, with
> intel_pstate=support_acpi_ppc in the cmdline:
> 
> turbostat version 18.06.20 - Len Brown <lenb@kernel.org>
> CPUID(0): GenuineIntel 13 CPUID levels; family:model:stepping
> 0x6:45:1 (6:69:1)
> CPUID(1): SSE3 MONITOR - EIST TM2 TSC MSR ACPI-TM HT TM
> CPUID(6): APERF, TURBO, DTS, PTM, No-HWP, No-HWPnotify, No-HWPwindow, 
> No-HWPepp, No-HWPpkg, EPB
> cpu0: MSR_IA32_MISC_ENABLE: 0x00850089 (TCC EIST MWAIT PREFETCH
> TURBO)
> CPUID(7): No-SGX
> cpu0: MSR_MISC_PWR_MGMT: 0x00400000 (ENable-EIST_Coordination
> DISable-EPB DISable-OOB)
> RAPL: 17476 sec. Joule Counter Range, at 15 Watts
> cpu0: MSR_PLATFORM_INFO: 0x8083df3011800
> 8 * 100.0 = 800.0 MHz max efficiency frequency
> 24 * 100.0 = 2400.0 MHz base frequency
> cpu0: MSR_IA32_POWER_CTL: 0x0004005d (C1E auto-promotion: DISabled)
> cpu0: MSR_TURBO_RATIO_LIMIT: 0x1b1b1b1e
> 27 * 100.0 = 2700.0 MHz max turbo 4 active cores
> 27 * 100.0 = 2700.0 MHz max turbo 3 active cores
> 27 * 100.0 = 2700.0 MHz max turbo 2 active cores
> 30 * 100.0 = 3000.0 MHz max turbo 1 active cores
> cpu0: MSR_CONFIG_TDP_NOMINAL: 0x00000012 (base_ratio=18)
> cpu0: MSR_CONFIG_TDP_LEVEL_1: 0x0008005c (PKG_MIN_PWR_LVL1=0
> PKG_MAX_PWR_LVL1=0 LVL1_RATIO=8 PKG_TDP_LVL1=92)
> cpu0: MSR_CONFIG_TDP_LEVEL_2: 0x001800c8 (PKG_MIN_PWR_LVL2=0
> PKG_MAX_PWR_LVL2=0 LVL2_RATIO=24 PKG_TDP_LVL2=200)
> cpu0: MSR_CONFIG_TDP_CONTROL: 0x00000000 ( lock=0)
> cpu0: MSR_TURBO_ACTIVATION_RATIO: 0x00000011 (MAX_NON_TURBO_RATIO=17
> lock=0)
> cpu0: MSR_PKG_CST_CONFIG_CONTROL: 0x1e008407 (UNdemote-C3, UNdemote-
> C1, demote-C3, demote-C1, locked, pkg-cstate-limit=7 (pc9))
> cpu0: POLL: CPUIDLE CORE POLL IDLE
> cpu0: C1: MWAIT 0x00
> cpu0: C1E: MWAIT 0x01
> cpu0: C3: MWAIT 0x10
> cpu0: C6: MWAIT 0x20
> cpu0: C7s: MWAIT 0x32
> cpu0: C8: MWAIT 0x40
> cpu0: C9: MWAIT 0x50
> cpu0: C10: MWAIT 0x60
> cpu0: cpufreq driver: intel_pstate
> cpu0: cpufreq governor: powersave
> cpufreq intel_pstate no_turbo: 0
> cpu0: MSR_MISC_FEATURE_CONTROL: 0x00000000 (L2-Prefetch L2-Prefetch-
> pair L1-Prefetch L1-IP-Prefetch)
> cpu0: MSR_IA32_ENERGY_PERF_BIAS: 0x00000006 (balanced)
> cpu0: MSR_CORE_PERF_LIMIT_REASONS, 0x1d210020 (Active: Auto-HWP, )
> (Logged: MultiCoreTurbo, PkgPwrL2, PkgPwrL1, Amps, Auto-HWP, PROCHOT,
> )
> cpu0: MSR_GFX_PERF_LIMIT_REASONS, 0x1c010000 (Active: ) (Logged:
> PROCHOT, PkgPwrL1, PkgPwrL2, )
> cpu0: MSR_RING_PERF_LIMIT_REASONS, 0x0d010000 (Active: ) (Logged:
> PROCHOT, Amps, PkgPwrL1, PkgPwrL2, )
> cpu0: MSR_RAPL_POWER_UNIT: 0x000a0e03 (0.125000 Watts, 0.000061
> Joules, 0.000977 sec.)
> cpu0: MSR_PKG_POWER_INFO: 0x00000078 (15 W TDP, RAPL 0 - 0 W,
> 0.000000 sec.)
> cpu0: MSR_PKG_POWER_LIMIT: 0x420078001480c8 (UNlocked)
> cpu0: PKG Limit #1: ENabled (25.000000 Watts, 1.000000 sec, clamp
> DISabled)
> cpu0: PKG Limit #2: DISabled (15.000000 Watts, 0.002441* sec, clamp
> DISabled)
> cpu0: MSR_PP0_POLICY: 0
> cpu0: MSR_PP0_POWER_LIMIT: 0x00000000 (UNlocked)
> cpu0: Cores Limit: DISabled (0.000000 Watts, 0.000977 sec, clamp
> DISabled)
> cpu0: MSR_PP1_POLICY: 0
> cpu0: MSR_PP1_POWER_LIMIT: 0x00000000 (UNlocked)
> cpu0: GFX Limit: DISabled (0.000000 Watts, 0.000977 sec, clamp
> DISabled)
> cpu0: MSR_IA32_TEMPERATURE_TARGET: 0x00640000 (100 C)
> cpu0: MSR_IA32_PACKAGE_THERM_STATUS: 0x882d0808 (55 C)
> cpu0: MSR_IA32_PACKAGE_THERM_INTERRUPT: 0x00000003 (100 C, 100 C)
> cpu0: MSR_IA32_THERM_STATUS: 0x882d0808 (55 C +/- 1)
> cpu0: MSR_IA32_THERM_INTERRUPT: 0x00000013 (100 C, 100 C)
> cpu2: MSR_IA32_THERM_STATUS: 0x88300808 (52 C +/- 1)
> cpu2: MSR_IA32_THERM_INTERRUPT: 0x00000013 (100 C, 100 C)
> cpu0: MSR_PKGC3_IRTL: 0x00008842 (valid, 67584 ns)
> cpu0: MSR_PKGC6_IRTL: 0x00008873 (valid, 117760 ns)
> cpu0: MSR_PKGC7_IRTL: 0x00008891 (valid, 148480 ns)
> cpu0: MSR_PKGC8_IRTL: 0x000088e4 (valid, 233472 ns)
> cpu0: MSR_PKGC9_IRTL: 0x00008945 (valid, 332800 ns)
> cpu0: MSR_PKGC10_IRTL: 0x00009003 (valid, 3 ns)
> 
> 
> And this is what I get after I unplug the laptop:
> 
> turbostat version 18.06.20 - Len Brown <lenb@kernel.org>
> CPUID(0): GenuineIntel 13 CPUID levels; family:model:stepping
> 0x6:45:1 (6:69:1)
> CPUID(1): SSE3 MONITOR - EIST TM2 TSC MSR ACPI-TM HT TM
> CPUID(6): APERF, No-TURBO, DTS, PTM, No-HWP, No-HWPnotify, No-
> HWPwindow, No-HWPepp, No-HWPpkg, EPB
> cpu3: MSR_IA32_MISC_ENABLE: 0x4000850089 (TCC EIST MWAIT PREFETCH No-
> TURBO)
> CPUID(7): No-SGX
> cpu3: MSR_MISC_PWR_MGMT: 0x00400000 (ENable-EIST_Coordination
> DISable-EPB DISable-OOB)
> RAPL: 17476 sec. Joule Counter Range, at 15 Watts
> cpu3: MSR_PLATFORM_INFO: 0x8083df3011800
> 8 * 100.0 = 800.0 MHz max efficiency frequency
> 24 * 100.0 = 2400.0 MHz base frequency
> cpu3: MSR_IA32_POWER_CTL: 0x0004005d (C1E auto-promotion: DISabled)
> cpu3: MSR_TURBO_RATIO_LIMIT: 0x1b1b1b1e
> 27 * 100.0 = 2700.0 MHz max turbo 4 active cores
> 27 * 100.0 = 2700.0 MHz max turbo 3 active cores
> 27 * 100.0 = 2700.0 MHz max turbo 2 active cores
> 30 * 100.0 = 3000.0 MHz max turbo 1 active cores
> cpu3: MSR_CONFIG_TDP_NOMINAL: 0x00000012 (base_ratio=18)
> cpu3: MSR_CONFIG_TDP_LEVEL_1: 0x0008005c (PKG_MIN_PWR_LVL1=0
> PKG_MAX_PWR_LVL1=0 LVL1_RATIO=8 PKG_TDP_LVL1=92)
> cpu3: MSR_CONFIG_TDP_LEVEL_2: 0x001800c8 (PKG_MIN_PWR_LVL2=0
> PKG_MAX_PWR_LVL2=0 LVL2_RATIO=24 PKG_TDP_LVL2=200)
> cpu3: MSR_CONFIG_TDP_CONTROL: 0x00000000 ( lock=0)
> cpu3: MSR_TURBO_ACTIVATION_RATIO: 0x00000011 (MAX_NON_TURBO_RATIO=17
> lock=0)
> cpu3: MSR_PKG_CST_CONFIG_CONTROL: 0x1e008407 (UNdemote-C3, UNdemote-
> C1, demote-C3, demote-C1, locked, pkg-cstate-limit=7 (pc9))
> cpu3: POLL: CPUIDLE CORE POLL IDLE
> cpu3: C1: MWAIT 0x00
> cpu3: C1E: MWAIT 0x01
> cpu3: C3: MWAIT 0x10
> cpu3: C6: MWAIT 0x20
> cpu3: C7s: MWAIT 0x32
> cpu3: C8: MWAIT 0x40
> cpu3: C9: MWAIT 0x50
> cpu3: C10: MWAIT 0x60
> cpu3: cpufreq driver: intel_pstate
> cpu3: cpufreq governor: powersave
> cpufreq intel_pstate no_turbo: 1
> cpu3: MSR_MISC_FEATURE_CONTROL: 0x00000000 (L2-Prefetch L2-Prefetch-
> pair L1-Prefetch L1-IP-Prefetch)
> cpu0: MSR_IA32_ENERGY_PERF_BIAS: 0x00000006 (balanced)
> cpu0: MSR_CORE_PERF_LIMIT_REASONS, 0x1d210000 (Active: ) (Logged:
> MultiCoreTurbo, PkgPwrL2, PkgPwrL1, Amps, Auto-HWP, PROCHOT, )
> cpu0: MSR_GFX_PERF_LIMIT_REASONS, 0x1c010000 (Active: ) (Logged:
> PROCHOT, PkgPwrL1, PkgPwrL2, )
> cpu0: MSR_RING_PERF_LIMIT_REASONS, 0x0d010000 (Active: ) (Logged:
> PROCHOT, Amps, PkgPwrL1, PkgPwrL2, )
> cpu0: MSR_RAPL_POWER_UNIT: 0x000a0e03 (0.125000 Watts, 0.000061
> Joules, 0.000977 sec.)
> cpu0: MSR_PKG_POWER_INFO: 0x00000078 (15 W TDP, RAPL 0 - 0 W,
> 0.000000 sec.)
> cpu0: MSR_PKG_POWER_LIMIT: 0x420078001480c8 (UNlocked)
> cpu0: PKG Limit #1: ENabled (25.000000 Watts, 1.000000 sec, clamp
> DISabled)
> cpu0: PKG Limit #2: DISabled (15.000000 Watts, 0.002441* sec, clamp
> DISabled)
> cpu0: MSR_PP0_POLICY: 0
> cpu0: MSR_PP0_POWER_LIMIT: 0x00000000 (UNlocked)
> cpu0: Cores Limit: DISabled (0.000000 Watts, 0.000977 sec, clamp
> DISabled)
> cpu0: MSR_PP1_POLICY: 0
> cpu0: MSR_PP1_POWER_LIMIT: 0x00000000 (UNlocked)
> cpu0: GFX Limit: DISabled (0.000000 Watts, 0.000977 sec, clamp
> DISabled)
> cpu0: MSR_IA32_TEMPERATURE_TARGET: 0x00640000 (100 C)
> cpu0: MSR_IA32_PACKAGE_THERM_STATUS: 0x882f0808 (53 C)
> cpu0: MSR_IA32_PACKAGE_THERM_INTERRUPT: 0x00000003 (100 C, 100 C)
> cpu0: MSR_IA32_THERM_STATUS: 0x882f0808 (53 C +/- 1)
> cpu0: MSR_IA32_THERM_INTERRUPT: 0x00000013 (100 C, 100 C)
> cpu2: MSR_IA32_THERM_STATUS: 0x88300808 (52 C +/- 1)
> cpu2: MSR_IA32_THERM_INTERRUPT: 0x00000013 (100 C, 100 C)
> cpu3: MSR_PKGC3_IRTL: 0x00008842 (valid, 67584 ns)
> cpu3: MSR_PKGC6_IRTL: 0x00008873 (valid, 117760 ns)
> cpu3: MSR_PKGC7_IRTL: 0x00008891 (valid, 148480 ns)
> cpu3: MSR_PKGC8_IRTL: 0x000088e4 (valid, 233472 ns)
> cpu3: MSR_PKGC9_IRTL: 0x00008945 (valid, 332800 ns)
> cpu3: MSR_PKGC10_IRTL: 0x00009003 (valid, 3 ns)
> 
> 
> MSR_CORE_PERF_LIMIT_REASONS seems to have a different value
> when plugged in depending on how the laptop booted. I don't
> know if this is relevant, but this is what I noticed.
> 
> Right after a reboot while plugged in, I get:
> cpu0: MSR_CORE_PERF_LIMIT_REASONS, 0x1d201000 (Active:
> MultiCoreTurbo, ) (Logged: MultiCoreTurbo, PkgPwrL2, PkgPwrL1, Amps,
> Auto-HWP, )
> If unplug and replug, I get:
> cpu0: MSR_CORE_PERF_LIMIT_REASONS, 0x1d210020 (Active: Auto-HWP, )
> (Logged: MultiCoreTurbo, PkgPwrL2, PkgPwrL1, Amps, Auto-HWP, PROCHOT,
> )
> 
> If the laptop booted while unplgged, I constantly get:
> cpu0: MSR_CORE_PERF_LIMIT_REASONS, 0x14000000 (Active: ) (Logged:
> MultiCoreTurbo, PkgPwrL1, )
> 
> 
> > Also output of acpidump?
> 
> You can find it here:
> https://bugzilla.kernel.org/attachment.cgi?id=178381
> 
> > 
> > > Plugged -> Unplugged:
> > > 
> > > [   40.046116] CPU 0: _PPC is 6 - frequency  limited
> > > [   40.046128] intel_pstate: policy->max > max non turbo
> > > frequency
> > > [   40.046131] intel_pstate: set_policy cpuinfo.max 3000000
> > > policy-
> > > > max 3000000
> > > 
> > > [   40.046134] intel_pstate: cpu:0 max_state 30 min_policy_perf:8
> > > max_policy_perf:30
> > > [   40.046137] intel_pstate: cpu:0 global_min:8 global_max:30
> > > [   40.046140] intel_pstate: cpu:0 max_perf_ratio:30
> > > min_perf_ratio:8
> > > [   40.162173] CPU 0: _PPC is 6 - frequency  limited
> > > [   40.162186] intel_pstate: policy->max > max non turbo
> > > frequency
> > > [   40.162190] intel_pstate: set_policy cpuinfo.max 3000000
> > > policy-
> > > > max 3000000
> > > 
> > > [   40.162194] intel_pstate: cpu:0 max_state 30 min_policy_perf:8
> > > max_policy_perf:30
> > > [   40.162197] intel_pstate: cpu:0 global_min:8 global_max:30
> > > [   40.162200] intel_pstate: cpu:0 max_perf_ratio:30
> > > min_perf_ratio:8
> > > [   40.162215] CPU 0: _PPC is 6 - frequency  limited
> > > [   40.162220] intel_pstate: policy->max > max non turbo
> > > frequency
> > > [   40.162223] intel_pstate: set_policy cpuinfo.max 3000000
> > > policy-
> > > > max 3000000
> > > 
> > > [   40.162226] intel_pstate: cpu:0 max_state 30 min_policy_perf:8
> > > max_policy_perf:30
> > > [   40.162228] intel_pstate: cpu:0 global_min:8 global_max:30
> > > [   40.162230] intel_pstate: cpu:0 max_perf_ratio:30
> > > min_perf_ratio:8
> > > [   40.162237] CPU 0: _PPC is 6 - frequency  limited
> > > [   40.162241] intel_pstate: policy->max > max non turbo
> > > frequency
> > > [   40.162243] intel_pstate: set_policy cpuinfo.max 3000000
> > > policy-
> > > > max 3000000
> > > 
> > > [   40.162245] intel_pstate: cpu:0 max_state 30 min_policy_perf:8
> > > max_policy_perf:30
> > > [   40.162247] intel_pstate: cpu:0 global_min:8 global_max:30
> > > [   40.162249] intel_pstate: cpu:0 max_perf_ratio:30
> > > min_perf_ratio:8
> > > [   40.162257] CPU 0: _PPC is 6 - frequency  limited
> > > [   40.162261] intel_pstate: policy->max > max non turbo
> > > frequency
> > > [   40.162263] intel_pstate: set_policy cpuinfo.max 3000000
> > > policy-
> > > > max 3000000
> > > 
> > > [   40.162265] intel_pstate: cpu:0 max_state 30 min_policy_perf:8
> > > max_policy_perf:30
> > > [   40.162267] intel_pstate: cpu:0 global_min:8 global_max:30
> > > [   40.162269] intel_pstate: cpu:0 max_perf_ratio:30
> > > min_perf_ratio:8
> > > 
> > > Unplugged -> Plugged:
> > > 
> > > [   52.648535] CPU 0: _PPC is 6 - frequency  limited
> > > [   52.648553] intel_pstate: set_policy cpuinfo.max 3000000
> > > policy-
> > > > max 1700000
> > > 
> > > [   52.648558] intel_pstate: cpu:0 max_state 17 min_policy_perf:8
> > > max_policy_perf:17
> > > [   52.648562] intel_pstate: cpu:0 global_min:8 global_max:30
> > > [   52.648566] intel_pstate: cpu:0 max_perf_ratio:17
> > > min_perf_ratio:8
> > > [   52.648583] CPU 0: _PPC is 6 - frequency  limited
> > > [   52.648590] intel_pstate: set_policy cpuinfo.max 3000000
> > > policy-
> > > > max 1700000
> > > 
> > > [   52.648595] intel_pstate: cpu:0 max_state 17 min_policy_perf:8
> > > max_policy_perf:17
> > > [   52.648598] intel_pstate: cpu:0 global_min:8 global_max:30
> > > [   52.648602] intel_pstate: cpu:0 max_perf_ratio:17
> > > min_perf_ratio:8
> > > [   52.656093] CPU 0: _PPC is 6 - frequency  limited
> > > [   52.656111] intel_pstate: set_policy cpuinfo.max 3000000
> > > policy-
> > > > max 1700000
> > > 
> > > [   52.656116] intel_pstate: cpu:0 max_state 17 min_policy_perf:8
> > > max_policy_perf:17
> > > [   52.656120] intel_pstate: cpu:0 global_min:8 global_max:30
> > > [   52.656123] intel_pstate: cpu:0 max_perf_ratio:17
> > > min_perf_ratio:8
> > > [   52.775577] CPU 0: _PPC is 6 - frequency  limited
> > > [   52.775594] intel_pstate: set_policy cpuinfo.max 3000000
> > > policy-
> > > > max 1700000
> > > 
> > > [   52.775598] intel_pstate: cpu:0 max_state 17 min_policy_perf:8
> > > max_policy_perf:17
> > > [   52.775601] intel_pstate: cpu:0 global_min:8 global_max:30
> > > [   52.775604] intel_pstate: cpu:0 max_perf_ratio:17
> > > min_perf_ratio:8
> > > [   53.028620] CPU 0: _PPC is 6 - frequency  limited
> > > [   53.028637] intel_pstate: set_policy cpuinfo.max 3000000
> > > policy-
> > > > max 1700000
> > > 
> > > [   53.028643] intel_pstate: cpu:0 max_state 17 min_policy_perf:8
> > > max_policy_perf:17
> > > [   53.028647] intel_pstate: cpu:0 global_min:8 global_max:30
> > > [   53.028651] intel_pstate: cpu:0 max_perf_ratio:17
> > > min_perf_ratio:8
> > > 
> > > > and send dmesg after you change power sources.
> > > > 
> > > > - Also try with
> > > > intel_pstate=disable dyndbg="file processor_perflib.c +p"
> > > 
> > > Nothing gets printed with this one.
> > > 
> > > Thanks,
> > > Gabriele
> > > 
> > > > and send dmesg.
> > > > 
> > > > Thanks,
> > > > Srinivas
> > > > 
> > > >